The document provides an overview of environmental entomology, focusing on the relationship between insects and their abiotic and biotic environments. It discusses interactions among species, including intraspecific and interspecific interactions, and various ecological relationships such as competition, predation, parasitism, and mutualism. Additionally, it highlights the significance of these interactions in shaping insect populations and ecosystems.

2. Topic:
IntroductionTo
Environmental Entomology

3. Insects and their environment:
Study of organisms in relation to their
environment
Modern science of ecology
Important for the study of evolution of
insects

4. Insects and their Abiotic
Environment:
Temperature
Moisture
Light
Other factors

5. Life system concept of Insects:
Part of the ecosystem that determines the existence
abundance and evolution of a particular population
Components of environment effects the insect
population
When one of them approaches the specific limit of
tolerance, relative to survival development and
fecundity than it become limiting factor

6. Insects and their Biotic
Environment:
Biotic environment consist of all living
things in an ecosystem.All plants, animals,
fungi and microbes in an environment are
its biotic components.

7. Interaction with Biotic
Environment:
When organisms interact with their environment
they also interact among themselves.
There are two types of interactions
Intraspecific Interaction
Interspecific Interaction

8. Intraspecific Interaction:
Within species
For
• Food
• Mates
• Breeding territories
• Space
• Light
• Minerals

9. Intraspecific interaction includes:
 Competition
• Population Density
• Birth Rate
• Death Rate
• Dispersion
• Growth Pattern

10. Competition:
When two or more organisms seek the
same resources e.g., Food,Water, Nesting
space, Ground space which are in limiting
supply, seeking it they compete with each
other.

11. Population Density:
Competition depends on Population density
The ways in which member of same species
interact with each other are related with
population density. Population density may
be lower and higher.

12. Dispersion:
To avoid competition
Due to shortage of resources in a
particular area the individuals of same
specie dispersed into various direction.

13. Interspecific Interaction:
Interaction among the individuals
of different species.
There are two types of interspecific interaction
Harmonious or Positive interaction
Inharmonious or Negative interaction

14. Interspecific Competition:
It arises when the needs of two or more different species
for given resources coincide with their overlapping niches.
When two species with identical needs compete, one
specie usually displaces the other and this is called
competitive displacement.
Example: Two species of flour beetle Tribolium
castaneum and Tribolium confusum placed in a container.
At high temperature & humidity T.castaneum displaces
T.confusum while at low temperature & humidity
T.confusum displaces T.castaneum.

15. Harmonious or Positive
Interaction:
Harmonious, or positive interaction is that in which none of the
participating beings is harmed.
It includes
Commensalism
Mutualism or symbiosis
Trophallaxis

16. Commensalism:
The interaction in which one specie is benefited and other is not harmed.
It is positive interaction.
Example: Some species of chewing lice (Mallophaga) ectoparasites of birds attached
by their mouthparts to louse flies (Diptera) are transported from one host to another.
Torsalo fly lays eggs on other flies such as mosquitoes, house flies. When these
insects come into with a vertebrate host the larva emerges from egg and penetrate
into host skin.

17. Mutualism:
In this association both species are benefited and
these species becomes completely dependent on
each others.
Example: Aphids and ants mutual relationship.
Pollinators Insects.

18. Trophalaxis:
Trophallaxis is the transfer of food or other fluids
among members of a specie through mouth-to-
mouth (stomodeal) or anus-to-mouth (proctodeal)
feeding.
It is most highly developed in social insects such
as ants, termites, wasps and bees.

19. Inharmonious or Negative
Interaction:It is sort of interaction in which atleast one
specie is being harmed.
It includes
Predation
Parasitism
Cannibolism
Ammensalism

20. Predation:
A predator is an animal that eats other animals.
Many insects are predatory.These insects are
often diurnal and have large compound eyes to
allow them to spot their prey.
Example: Dragon flies, Mantids, Beetles,

21. Parasitism:
Insects which lives “in” or “on” the body of other organisms
and insects are known as parasites & the phenomenon is
known as parasitism.
Types of parasites on the basis of their hosts
Parasites of vertebrates
Parasites of other insects and arthropods

22. Vertebrates parasites:
Vertebrates parasites are sucking lice, chewing lice,
true bugs, true flies and fleas.
They are further divided into two groups
Ectoparasites: Lives on the external surface of host
Endoparasites: Lives inside the body of host

23. Parasites of Insects:
Many insects are parasites of other insects. For
example Strepsipterans twisted wings parasites
spend their whole life within the host insect.
Many insects larvae parasitize other insects and
eventually after destroying their host become free
living adults.They are called parasitoids.

24. Types of parasitism:
Primary parasitism
Secondary parasitism
Tertiary parasitism

25. Cannibalism:Cannibalism, also known as intraspecific predation,
is the process of killing and consuming an individual
of the same species.
Sexual Cannibalism:
Sexual cannibalism is when a
female cannibalizes her mate prior to, during, or
after copulation. It is a phenomenon characterized
primarily by members of most arachnid orders, as
well as several insects orders.

26. Ammensalism:
Ammensalism is the ecological interaction in which an
individual species harms other without obtaining benefit.
Ammensalism is an inharmonious (negative) ecological
interaction since one participant is harmed.
One of the best Examples of ammensalism is the one
established between humans and other species under
extinction due to human actions like habitat devastation
by fires, ecological accidents, leisure hunting, etc.